Udev calls the script twice for some reason on the system described below.

At first, udev calls hplj1000 with "/dev/bus/usb/004/059" as a $DEVNAME which is not desired/not supported.
Then it calls the script once again with "/dev/usb/lp0" as a $DEVNAME which is desired and must be used to load a firmware to.

The problem is that the script handles only "/dev/usb/usb*" case but not the "/dev/bus/usb/*".
This leads to firmware being loaded twice which causes HP LaserJet 1000 to hang and stop processing tasks.

Attached patch adds another case to the /lib/udev/hplj1000 script that silently exits if the script is called with undesired value.